Just over one fifth of respondents instead recommended building low-emission products as the top priority, when asked for their advice to a $200-billion venture capital fund looking to limit global warming to 2 °C above pre-industrial levels within the next 20 years.

As with previous Vision Prize polls, the experts surveyed agreed with each other more than they thought they would, with the most common views tending to be even more common than expected. Vision Prize asks respondents for their answer to each question, as well as how they believe their peers will react. Poll participants are pre-screened to ensure they have relevant expertise.

Coal emissions

The bulk of survey participants (84%) expect that coal-fired power plants will contribute between 25 and 60% of gross carbon emissions to the atmosphere between now and 2020, the Vision Prize poll for the second quarter of 2014 found.

In June the US Environmental Protection Agency introduced regulations that aim to cut carbon pollution from power plants by 30% from 2005 levels by 2030. The rules will be applied state by state.

But what did the experts think would be most likely to provide an alternative source of energy to coal? Just over two-thirds agreed with the open letter by Ken Caldeira, Kerry Emanuel, James Hansen and Tom Wigley in November 2013 stating that renewables like wind, solar and biomass will not be able to scale up fast enough to deliver cheap and reliable power at the scale the global economy requires. And 71% agreed with Caldeira and colleagues that "there is no credible path to climate stabilization that does not include a substantial role for nuclear power."

environmentalresearchweb blogger David Elliott, emeritus professor at the Open University, UK, is surprised by these findings because polls of public opinion have usually indicated strong opposition to nuclear in most countries except the US and UK, coupled almost everywhere with strong support for renewables.

"Does the Vision poll mean the public have got it wrong?" he asked. "Are they just reacting subjectively to nuclear horror stories and indulging in wishful thinking about renewables? For what it's worth, my own view is that, on one hand, it is reasonable to be concerned about producing more radioactivity, especially given that we have as yet no long-term waste-disposal sites available anywhere in the world and security threats proliferate. And, on the other hand, I suggest the assertion that 'renewables can't deliver' is just that – an assertion."

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